cxgb3: Handle ARP completions that mark neighbors stale.

When ARP completes due to a request rather than a reply the neighbor is
marked NUD_STALE instead of reachable (see arp_process()).  The handler
for the resulting netevent needs to check also for NUD_STALE.

Failure to use the arp entry can cause RDMA connection failures.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/cxgb3/l2t.c

@@ -404,7 +404,7 @@ found:
 			if (neigh->nud_state & NUD_FAILED) {
 				arpq = e->arpq_head;
 				e->arpq_head = e->arpq_tail = NULL;
-			} else if (neigh_is_connected(neigh))
+			} else if (neigh->nud_state & (NUD_CONNECTED|NUD_STALE))
 				setup_l2e_send_pending(dev, NULL, e);
 		} else {
 			e->state = neigh_is_connected(neigh) ?